Patent GB-190908259-A (GB)
Title: Improvements in and relating to Calculating Machines.
Inventor: BARR MARK
Filed: 1909-04-06
Granted: 1910-04-06
Abstract: 8259. Barr, M., and Clarke, E. R. April 6. Multiplying apparatus.. -In a machine for performing, without successive action, various operations of multiplication such as between pure numbers, between a price expressed in pounds, shillings, and pence, and either a n u m b e r , or another quantity such as a weight expressed in tons, cwts., &c., and also for calculating interest, percentage, and the like, levers are provided to set the multiplicand and the multiplier, movements proportional to the digits so set being transformed by a differential pulley or equivalent into the rotation of disks shaped according to the partial products, which, for the corresponding denomination, are then a d d e d together by a single linear movement and transmitted through a device to the indicating-disks, the latter device serving as a means greatly to reduce the number of operations of carrying. A part elevation of the machine adapted for multiplying a price by a number is shown in Figs. 1 and 2, and a part side elevation in Fig. 3. The digits of the two factors are set by the levers 1, which terminate at their other ends in circular arcs 3, 6 connected by wires to pulleys 4, 7 on the shafts p, q, r, s, a, b, c, d. On each of the shafts p, q, r, s, four pulleys 5 are mounted, arranged in sixteen pairs with four pulleys 8 on each of the shafts a, b, c, d. A wire 9 passes round a pair of pulleys and round a differential pulley 10 suspended by a wire 11 from a pulley 12 under the control of a spring pulley 14. To each of the pulleys 12 is attached a number of partial-product disks S, depending on the number of denominations affected by the class of computation to be undertaken, and provided with notches to represent the particular partial products ; the depth of these notches can be felt or measured by pins 22 on levers F, pivoted on rods 21. The levers F are held in the normal position, Fig. 3, by rods 32, toggle-bars 33, and a lever 34, the lever being rocked from the main handle 65 by the engagement of a pin 75 thereon with slots 71, 72 in the cam 70. Wires 23 are attached to the other ends of the levers F, and pass over pulleys 24, Fig. 2, and a pulley 26, which thus receives a movement depending on the sum of the movements of the pulleys 24. To this pulley a wire 27 is attached, which passes round the pulley 28 under the tension of the spring pulley 30, so that further stepped disks C may receive the movement of the corresponding pulley 26. The disks C have two stepped parts, one for units and the other for tens, whereby a sum in excess of nine of the digits of a particular column of partial products is distributed to the denominations concerned in order that the number of operations of transfer may be greatly reduced at the indicating- disks, no transfer there being greater than unity. The depth of the notches in the disks C are felt or measured by pins 42 on the levers 41, which receive their movement from the main handle, after the disks C have been set, owing to engagement of the pin 76 with the slots 71, 72, whereby the lever 62 rises, and consequently the lever 41. The movement is transmitted to a pulley 46 by a wire 45, which passes from the tens lever of one denomination to the units lever of the next higher denomination. Each pulley 46 is suspended by a wire 47, which is led over the pulleys 48, 53, 54 to the indicating-wheels 55 under tension from the spring pulley 58. The transfer between the indicating-wheels may be of any known kind.